Implantable Medical Devices and Related Connector Enclosure Assemblies Utilizing Conductors Electrically Coupled to Feedthrough Pins

ABSTRACT

Implantable medical devices include connector enclosure assemblies that utilize conductors electrically coupled to feedthrough pins that extend into a can where electrical circuitry is housed. The conductors may be coupled to the feedthrough pins and to capacitor plates within a filter capacitor by an electrically conductive bonding material and as a single bonding event during manufacturing. The base plate of the connector enclosure assembly may also include a ground pin. Ground capacitor plates may be present at a ground aperture of the filter capacitor where the ground pin passes through so that the ground pin, a ground conductor, and the ground capacitor plate may be coupled. A protective cover may be provided for the connector enclosure assembly to enclose the conductors intended to extend into the can prior to the assembly being joined to the can. Conductors may be attached to a common tab that is subsequently removed.

TECHNICAL FIELD

Embodiments are related to implantable medical devices and connectorassemblies for implantable medical devices. More particularly,embodiments are related to implantable medical devices and connectorenclosure assemblies that use conductors electrically coupled tofeedthrough pins.

BACKGROUND

Implantable medical devices conventionally include a connector enclosurewhere the connectors mate to medical lead contacts and further include acan that houses the electrical circuitry. In these conventional devices,a top plate seals the can and exposes feedthrough pins that extend outof the can. The connector enclosure sits atop the top plate and receivesthe feedthrough pins where they connect to lead frame conductors thatinterconnect the feedthrough pins to the electrical connectors. Thus,during manufacturing, the feedthrough assembly is a part of the canassembly and the connector assembly is then added to complete thedevice, typically by creating the electrical connections for theconnector assembly and then forming the connector enclosure over theconnections using a polymer.

Within the can of the convention medical device, the feedthrough pinspass through and are bonded to a filter capacitor that provides acapacitive coupling to the can to filter out unwanted electromagneticinterference signals from entering into the device. The feedthrough pinsincluding a pin dedicated for establishing an electrical ground for theelectrical circuitry within the can would then be laser welded to afeedthrough contact. A flexible circuit portion interconnects thefeedthrough contact to the circuit board that contains the electricalcircuitry of the device.

This conventional approach has less appeal as device designs continue toget smaller. The amount of space required to bond the feedthrough pinsto the filter capacitor and then bond the feedthrough pins to theunderlying feedthrough contact limit the amount of miniaturization thatmay occur in the area of the feedthrough connections within the can.Furthermore, these feedthrough manufacturing operations require valuabletime and resources to accomplish. In some cases, even the flexiblecircuit may be an undesirable cost in terms of resources and spacerequirements.

SUMMARY

Embodiments address issues such as these and others by providing variousfeatures related to interconnections of the feedthrough pins to theelectrical circuitry within the can. In one or more embodiments, thefeedthrough pins and filter capacitor may be included in the manufactureof a connector enclosure assembly that is subsequently mounted to thecan. In particular, embodiments may provide an interconnection of afeedthrough pin, a filter capacitor, and a conductor intended to extendinto the can with an electrically conductive bonding material such assolder and the bond may occur as a single event of the manufacturingprocess. Embodiments may provide features such as ground pins that areintegral to a base plate of the connector enclosure assembly.Embodiments may provide features such as a support body that partiallycontains the conductor intended to extend into the can. Embodiments mayprovide features such as an internal ground plate within the filtercapacitor that establishes an interconnection to the ground pin.Embodiments may provide features such as a protective body that attachesto the connector enclosure assembly during a period prior to attachmentof the assembly to the can to enclose and protect the conductor that isintended to extend into the can. Embodiments may provide conductorsattached to a common tab that is later removed during assembly.

Embodiments provide an implantable medical device that includes aconnector enclosure including a base plate having an aperture, theconnector enclosure housing at least one electrical connector. A can iscoupled to the base plate, the can housing electrical circuitry. Afilter capacitor is coupled to the base plate, the filter capacitorhaving an aperture and having capacitor forming plates including aground plate, the ground plate being electrically coupled to the can. Afeedthrough pin is electrically coupled to the electrical connectorwithin the connector enclosure, the feedthrough pin extending throughthe aperture in the base plate and being present in the vicinity of theaperture in the filter capacitor. A conductor has a first end beingpresent in the vicinity of the aperture within the filter capacitor andhas a second end extending into the can and electrically coupled to theelectrical circuitry. An electrically conductive bonding material ispresent within the aperture of the filter capacitor and creates anelectrically conductive bond among the conductor, the feedthrough pin,and at least one of the capacitor forming plates other than the groundplate.

Embodiments provide a method of manufacturing a connector enclosureassembly of an implantable medical device that involves providing aconnector enclosure including a base plate having an aperture, theconnector enclosure housing at least one electrical connector. Themethod further involves providing a filter capacitor coupled to the baseplate, the filter capacitor having an aperture and having capacitorforming plates; providing a feedthrough pin electrically coupled to theelectrical connector within the connector enclosure, the feedthrough pinextending through the aperture in the base plate and being present inthe vicinity of the aperture in the filter capacitor; and providing aconductor with a first end being present in the vicinity of the aperturewithin the filter capacitor and with a second end extending away fromthe filter capacitor. Additionally, the method involves creating asingle electrically conductive bond among the conductor, the feedthroughpin, and at least one of the capacitor forming plates.

Embodiments provide an implantable medical device that includes aconnector enclosure including a base plate having an aperture and anintegral ground pin, the connector enclosure housing at least oneelectrical connector. A can is coupled to the base plate, the canhousing electrical circuitry. A fitter capacitor is coupled to the baseplate, the filter capacitor having an aperture and having capacitorforming plates including a ground plate, the ground plate beingelectrically coupled to the ground pin of the base plate. A feedthroughpin is electrically coupled to the electrical connector within theconnector enclosure, the feedthrough pin extending through the aperturein the base plate and being electrically coupled to a filter capacitorother than the ground plate. A first conductor has a first end beingelectrically coupled to the feedthrough pin and the filter capacitorother than the ground plate and has a second end extending into the canand electrically coupled to the electrical circuitry. A ground conductorhas a first end being electrically coupled to the integral ground pinand has a second end extending into the can and electrically coupled tothe electrical circuitry.

Embodiments provide an implantable medical device that includes aconnector enclosure including a base plate having an aperture, theconnector enclosure housing at least one electrical connector. A can iscoupled to the base plate, the can housing electrical circuitry. Afilter capacitor is coupled to the base plate, the filter capacitorhaving an aperture and having capacitor forming plates including aground plate, the ground plate being electrically coupled to the can. Afeedthrough pin is electrically coupled to the electrical connectorwithin the connector enclosure, the feedthrough pin extending throughthe aperture in the base plate and being electrically coupled to atleast one filter capacitor. A support body has a coupling to the baseplate, the support body having a conductor passing through, theconductor having a first end extending from the support body on one sideand a second end extending from the support body on another side, thefirst end being electrically coupled to the filter capacitor and thefeedthrough pin and the second end extending into the can and beingelectrically coupled to the electrical circuitry.

Embodiments provide an implantable medical device that includes aconnector enclosure including a base plate having an aperture and aground pin, the connector enclosure housing at least one electricalconnector. A can is coupled to the base plate, the can housingelectrical circuitry. A filter capacitor is coupled to the base plate,the filter capacitor having a ground aperture and having capacitorforming plates including a ground plate, the ground plate extending tothe ground aperture. A feedthrough pin is electrically coupled to theelectrical connector within the connector enclosure, the feedthrough pinextending through the aperture in the base plate and being electricallycoupled to a filter capacitor other than the ground plate. A firstconductor has a first end being electrically coupled to the feedthroughpin and the filter capacitor other than the ground plate and has asecond end extending into the can and electrically coupled to theelectrical circuitry. A ground conductor has a first end beingelectrically coupled to the integral ground pin and the ground plate andhas a second end extending into the can and electrically coupled to theelectrical circuitry. An electrically conductive bonding material ispresent within the ground aperture of the filter capacitor and createsan electrically conductive bond among the ground conductor, the groundpin, and the ground plate.

Embodiments provide a connector enclosure assembly for an implantablemedical device that includes a connector enclosure including a baseplate having an aperture, the connector enclosure housing at least oneelectrical connector. A filter capacitor is coupled to the base plate,the fitter capacitor having an aperture and having capacitor formingplates. A feedthrough pin is electrically coupled to the electricalconnector within the connector enclosure, the feedthrough pin extendingthrough the aperture in the base plate and being present in the vicinityof the aperture in the filter capacitor. A conductor has a first endbeing present in the vicinity of the aperture within the filtercapacitor and has a second end extending away from the filter capacitor,the first end being electrically coupled to the filter capacitor and thefeedthrough pin. A protector body is affixed to the base plate, theprotector body enclosing the conductor while having an apertureproviding access to the conductor.

Embodiments provide a connector enclosure assembly for an implantablemedical device. The connector assembly includes a connector enclosureincluding a base plate having a plurality of apertures and furtherincludes a filter capacitor coupled to the base plate, the filtercapacitor having a plurality of apertures and having capacitor formingplates. The connector enclosure assembly includes a plurality of feedthrough pins extending through the apertures in the base plate and inthe filter capacitor and also includes a plurality of conductors with afirst end of each conductor having an annular ring that surrounds acorresponding feedthrough pin in proximity to the filter capacitor witha second end of the plurality of conductors extending away from thefilter capacitor and being joined to a common tab.

Embodiments provide a method of manufacturing a connector enclosureassembly of an implantable medical device. The method involves providinga connector enclosure including a base plate having a plurality ofapertures and providing a filter capacitor coupled to the base plate,the filter capacitor having a plurality of apertures and havingcapacitor forming plates. The method further involves providing aplurality of feedthrough pins extending through corresponding aperturesin the base plate and in the filter capacitor. Additionally, the methodinvolves positioning a plurality of conductors with a first end of eachconductor having an annular ring that surrounds a correspondingfeedthrough pin in proximity to the filter capacitor with a second endof the plurality of conductors extending away from the filter capacitorand wherein the plurality of conductors are positioned by the secondends having a connection to a common tab.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an implantable medical system according to variousembodiments.

FIG. 2 shows an example of implantable medical device with a portion ofa can removed to reveal interior features.

FIG. 3 shows the implantable medical device with a connector enclosureremoved to further reveal interior features.

FIG. 4 shows a top view of a base plate and feedthrough pins of aconnector enclosure assembly of the implantable medical device.

FIGS. 5A and 5B show a bottom view of a base plate, feedthrough pins,and related conductors of a connector enclosure assembly of theimplantable medical device.

FIG. 6 shows a front-to-back cross-sectional view taken through the baseplate to reveal a mounting post of a support body of the connectorenclosure assembly.

FIG. 7 shows a side-to-side cross-sectional view taken through the baseplate to reveal an integral ground pin of the base plate as well as thefeedthrough pins and related conductors of the support body.

FIG. 8 shows a front-to-back cross-sectional view taken through the baseplate to reveal the interconnection of the feedthrough pin, relatedconductor, and filter capacitor.

FIG. 9 shows a front-to-back cross-sectional view taken through the baseplate to reveal the interconnection of the integral ground pin, relatedconductor, and filter capacitor.

FIG. 10 shows the support body and conductors that pass therethrough.

FIG. 11 shows the filter capacitor and related apertures.

FIG. 12 shows a bottom view of the connector enclosure assembly with thesupport body removed to reveal the filter cap.

FIG. 13 shows a view of the base plate portion of the connectorenclosure assembly with a protective body attached thereto.

FIG. 14 shows an exploded view of the protective body.

FIG. 15 shows a front-to-back cross-sectional view of the base plate andprotection body.

FIG. 16 shows a view of the connector enclosure assembly with theprotective body attached thereto.

FIG. 17 shows a view of an embodiment where conductors are joined at acommon tab and positioned for mounting to the feedthrough pins.

FIG. 18 shows a view of the embodiment where the conductors that arejoined at the common tab being soldered.

FIG. 19 shows an embodiment where washers are positioned about thefeedthrough pins.

FIG. 20 shows the embodiment where the conductors that are joined at thecommon tab are positioned at the washers for mounting to the feedthroughpins.

FIG. 21 shows a connector enclosure assembly with the conductorssoldered in place and the common tab removed.

FIG. 22 shows the connector assembly being attached to a remainder of amedical device after the common tab has been removed from theconductors.

FIG. 23 shows a cross-sectional view of an embodiment where conductorsare joined to feedthrough pins at a filter capacitor and the filtercapacitor includes a notch.

DETAILED DESCRIPTION

Embodiments provide implantable medical devices that include variousfeatures related to the electrical connectivity of a connector enclosureassembly containing electrical connectors to a can that houseselectrical circuitry. For example, the features may include feedthroughpins that are interconnected to conductors and filter capacitors via acommon electrically conductive bonding material, where the electricalbond that provides the interconnection may be done as a single stepduring manufacturing. As other examples, the features may include anintegral ground pin in a base plate and/or a filter capacitor thatprovides a ground plate that interconnects to a ground pin. Otherexamples include the apertures within the filter capacitor that receiveboth the feedthrough pin and a conductor intended to extend into thecan, where those apertures may have a shape such as a keyhole, and/orthe filter capacitor may include an asymmetric shape that is receivedwithin a matching recess of the base plate. Additional examples includea protective body that attaches to the base plate to protect theconductors that are intended to extend into the can prior to theconnector enclosure assembly being mounted to the can. Furthermore, insome embodiments, the conductors may be attached to a common tab that islater removed during assembly.

FIG. 1 shows an implantable medical device (IMD) system 100 thatincludes an IMD 102 and an implantable medical lead 104. The IMD 102 maybe of various types, such as a device for producing electricalstimulation and/or for sensing physiological signals for various medicalapplications such as neurological or cardiac therapy. The implantablemedical lead 104 includes a proximal end 112 of a lead body where aseries of electrical contacts 114 are located. Each electrical contacthas a corresponding conductor within the lead body that extends to adistal end (not shown) where a series of electrodes are present.

The implantable medical lead 104 is implanted into the body with thedistal end being routed to a desired location such that the electrodescontact the tissue of interest. The proximal end 112 is inserted into aconnector enclosure assembly 106 of the IMD 102 via an entryway 110.Within the connector enclosure assembly 106, electrical connectors makecontact with each of the contacts 114. Electrical circuitry within thecan 108 provides stimulation signals and/or monitors for sensed signalsby being electrically connected to the connectors within the connectorenclosure assembly 106. The electrical circuitry is thereby alsoconnected to the electrodes at the distal end of the implantable medicallead 104 such that the stimulation signals may be provided to tissue atthe electrodes and/or sensed signals may be obtained from the tissue.

In this particular example, the can 108 relies on separate components tocreate a hermetically sealed enclosure for the electrical circuitry.Namely, the can 108 relies on a bottom cap 116 that may be welded inplace or may be formed integrally with the can 108 and relies on a baseplate 130 which is shown in FIG. 2 that is a component of the connectorenclosure assembly 106 in this example. During manufacturing, theconnector enclosure assembly 106 is joined to the can 108 by the baseplate 130 being bonded such as by a weld to the top edge of the can 108.The can 108, bottom cap 116, and the connector assembly 106 includingthe base plate 130 may be made of rigid biocompatible materials such asvarious grades of titanium.

FIG. 2 shows the IMD 102 with one side of the can 108 removed to revealinner components. In this example, the IMD 102 includes a battery 120and electrical circuitry 122 housing within an isolation cup 118. Theisolation cup 118 may securely hold the components within the can 108while isolating the components from contact with the can 108. Theisolation cup 118 may be constructed of an insulator such as a liquidcrystal polymer.

In this particular example, the electrical circuitry 122 includeselectrical contact pads 124. Conductors 126 that extend from theconnector enclosure assembly 106 align with and are bonded to theelectrical contact pads 124 such as by soldering or a spot weld or thelike during assembly of the IMD 102. As discussed in more detail below,these conductors 126 provide electrical connectivity between theelectrical circuitry 122 and feed through pins, where the feedthroughpins provide electrical connectivity to the electrical connectors withinthe connector enclosure assembly 106.

As the conductors 126 extend from the feedthrough pins 136 to thecontact pads 124 in this example, there is no need for a flexiblecircuit to provide the interconnection. Accordingly, the structure forinterconnecting the flexible circuit to the feedthrough pins is omitted.

The conductors 126 pass through a support body 128 that is affixed tothe underside of the base plate 130. The support body 128 holds theconductors in proper positioning for interconnection to the feedthroughpins of the connector enclosure assembly 106 and also in proper positionfor bonding to the contact pads 124 of the electrical circuitry 122within the can 108. The support body 128 is discussed in more detailbelow with reference to FIG. 10. A discussion of the assembly of thedevice 102 is also discussed in more detail below.

FIG. 3 shows the IMD 102 with the connector enclosure removed to revealthe set of electrical connectors 132, a set screw 134, and feedthroughpins 136. The connector enclosure which has been removed may beconstructed of a polymer that is molded over the components shown inFIG. 3 or may be machined from a metal. For examples where the connectorenclosure is machine from metal, passageways are include that allow thefeedthrough pins 136 to avoid contact with the metal enclosure walls,while the set of connectors 132 are surrounded by an insulatorseparating the connectors 132 from the metal enclosure walls.Furthermore, the interior of the connector enclosure may be filled withan insulator such as a silicone to further insulate conductors from themetal enclosure. In this particular example, the feedthrough pins extendup to the connectors 132 and make electrical connection with theconnectors 132. It will be appreciated that in other examples, there maybe an intervening electrically conductive structure to interconnect thefeedthrough pins 136 and the connectors 132.

FIG. 4 shows a top view of the connector enclosure assembly with theconnector enclosure and the connectors 132 removed to reveal the top ofthe base plate 130. The feedthrough pins 136 can be seen rising fromapertures 138 within the base plate 130. These apertures 138 may includea ferrule 140 or other similar structure that includes an insulator 141such as a nonconductive polymer which surrounds the feedthrough pin 136to support the feedthrough pin within the aperture 138, create a sealbetween the feedthrough pin 136 and the base plate 130, and to isolatethe feedthrough pin 136 from contact with the base plate 130.

In FIG. 4, the insulator material 141 has been removed to reveal afilter capacitor 146 that lies underneath the base plate 130. The filtercapacitor 146 may be used to provide a filtered feedthrough by includingcapacitively coupled plates, where the interconnected feedthrough pin136 and conductor 126 are capacitively coupled to ground to remove EMIsignals from entering device. This capacitive coupling is discussed inmore detail below.

The filter capacitor 146 has an aperture 142 that allows the feedthroughpin 136 to pass through. In this particular example, the aperture 142also includes a region 144 that allows the conductor 126 to enter intothe aperture 142 such that the feedthrough pin 136 and conductor 126 areadjacent within the aperture 142, in this particular example, the regionis smaller than the portion of the aperture 142 where the feedthroughpin 136 passes such that the aperture 142 has a keyhole shape.

The conductor 126 and the feedthrough pin 136 are in the vicinity of oneanother as well as in the vicinity of the aperture 142. In thisparticular example, both the conductor 126 and the feedthrough pin 136are present within the aperture 142. Because the conductor 126 and thefeedthrough pin 136 are in the vicinity of one another and in thevicinity of the aperture 142, the conductor 126 and the feedthrough pin136 may be bonded together as well as to the filter capacitor 146 via asingle bonding event, as opposed to a separate bonding event for theconductor and a separate bonding even for the feedthrough pin.Furthermore, the non-ground capacitor plates within the filter capacitor146 may be present at the non-ground aperture 142 such that the bond mayalso occur with the non-ground capacitor plates as shown below in FIG.8. Thus, a single bonding event creates an electrical connection amongthe feedthrough pin 136, the conductor 126, and the non-ground capacitorplate of the filter capacitor 146 while creating a physical connectionamong feedthrough pin 136, conductor 126, and filter capacitor 146.

The filter capacitor 146 may be a ceramic material with conductive layerwithin to provide the capacitance. The aperture 142 may have a bordersuch as silver-palladium or Ni—Au plating or the like sputtered orotherwise attached to the ceramic about the aperture 142 so that anelectrically conductive bonding material may be used to bond theconductor 126, the feedthrough pin 136, and the filter capacitor 146together. For example, a solder joint 148 may be created at the junctionof the conductor 126, the feedthrough pin 136, and the filter capacitor146.

FIGS. 5A and 5B show the underside of the base plate 130 with theconnector enclosure assembly 106 being free from the can 108. A solderjoint 148 is present at the junction of a conductor, a pin, and thefilter capacitor 146. The filter capacitor 146 itself may be mechanicaland electrically bonded to the base plate 130 via a bonding material150, such as solder where the edge of the filter capacitor has a metalsputtered in place or otherwise attached to the ceramic such that thebonding material 150 such as solder bonds to the filter capacitor 146and to the base plate 130.

FIG. 5A shows the underside prior to the bond being created among thefeedthrough pin 136, conductor 126, and filter capacitor 146. Thebonding material, such as solder, may have a preformed shape. In thisexample, the preformed shape 149 includes a split where the conductor126 is positioned prior to heating the preformed shape 149. Uponheating, the preformed shape 149 becomes the bonded material 148 of FIG.5B.

For purposes of illustration, in FIG. 5B the solder is omitted for oneof the junctions of the feedthrough pin 136 and conductor 126 to revealthe keyhole shaped aperture 142 with the feedthrough pin 136 andconductor 126 being present at the aperture 142. FIG. 5B also shows oneview of the alignment of the support body 128 and the filter capacitor146. In this example, the support body 128 includes protrusions 152 thatoccur between each of the apertures 142 of the filter capacitor 146.

FIG. 6 shows a cross-sectional view further illustrating therelationship of the support body 128 to the filter capacitor 146 and thebase plate 130. Here it can be seen that the support body 128 of thisexample includes a mounting post 164. The mounting post 164 is press fitinto a cavity 154 within the base plate 130. This press fit holds thesupport body 128 in a fixed position with respect to the base plate 130,and also provides additional support for the filter capacitor 146 as thesupport body 128 contacts the underside of the filter capacitor 146.

FIG. 6 also shows the ferrule 140 that separates the nonconductivepolymer 141 not shown in this view and the feedthrough pin 136 from thebase plate 130. FIG. 6 also shows a separate insulator 158 that ispresent beneath the ferrule 140 and that is located between thefeedthrough pin 136 and the base plate 130. Additionally, a coating of anonconductive material 155 such as a medical adhesive can be seen atopthe base plate 130 covering the area where the feedthrough pins 136 passinto the base plate 130.

FIG. 7 shows another cross-sectional view of the base plate 130 and thefilter capacitor 146. FIG. 7 shows another view of the relationshipbetween the medical adhesive 155, the ferrule 140, the nonconductivepolymer 141, the insulator 158, and the feedthrough pin 136. This viewalso reveals that the base plate 130 of this particular example includesan integral ground pin 160. This integral ground pin 160 may be machinedas a feature of the base plate 130. As an alternative, a ground pin 160could be welded or otherwise attached to the base plate 130.

A ground conductor 162 is interconnected within the ground pin 160 viaan electrically conductive bond at a ground aperture of the filtercapacitor 146. Thus, the electrically circuitry 122 has a ground to thebase plate 130 which will ultimately be electrically connected to thecan 108 upon welding of the base plate 130 to the can 108. Furthermore,the ground aperture of the filter capacitor 146 may include the groundplates of the capacitive coupling present within the filter capacitor146 such that the electrically conductive bond also occurs with theground plates, which is discussed in more detail below with reference toFIG. 9. Therefore, in a single bonding event, an electrically conductivebond may occur among the ground pin 160, a ground conductor 162, and theground capacitor plate of the filter capacitor 146 while a physical bondmay also occur among the ground pin 160, the ground conductor 162, andthe filter capacitor 146.

FIG. 8 shows another cross-sectional view which illustrates an examplewhere the feedthrough pin 136 and the conductor 126 are both presentwithin the aperture 142 of the filter capacitor 146. Here, thenon-ground capacitor plates 172 and the ground capacitor plates 170 canbe seen within the filter capacitor 146, and the electrically conductivebond material 148 such as solder can also be seen filling the apertureand creating the electrical connection between the feedthrough pin 136,the conductor 126, and the non-ground capacitor plates 172. As can alsobe seen the ground capacitor plates 170 are electrically connected tothe base plate 130.

FIG. 9 shows another cross-sectional view which reveals details of theground aperture of the filter capacitor 146. Here it can be seen thatthe ground plates 170 are present at the ground aperture of the filtercapacitor 146 such that the ground pin 160, ground conductor 162, andthe ground plates 170 are electrically interconnected via theelectrically conductive bonding material 148. In this case, there is adirect ground path from the electrical circuitry 122 to the groundplates 170 through this junction established by the electricallyconductive bonding material 148.

FIG. 10 shows details of the support body 128 and conductors 126, 162.Here it can be seen that the conductors pass through the support body128, such as into one side and out another. In this case, the conductors126, 162 pass through a bottom side and out a front side but it will beappreciated that the conductors 126, 162 could pass through other sidesof the support body 128. As the support body 128 contains theconductors, the support body 128 is constructed of an insulator such aspolyether ether ketone (PEEK).

The support body 128 includes the posts 164 as well as protrusions 166that abut the base plate 130 to create proper spacing between thesupport body 128 and the base plate 130 where the filter capacitor 146resides. The support body also includes the protrusions 152 whichproperly position the support body 128 by abutting the filter capacitor146 to align the interfacing surfaces.

FIG. 11 shows the filer capacitor 146. This view further illustrates theasymmetric shape of this particular example as discussed above. Thisview also further illustrates the apertures 142 of this example, andparticularly the keyhole shape of the apertures 142 having the smallerdiameter portion 144.

FIG. 12 shows the underside of the base plate 130 and the filtercapacitor 146 with the support body 128 omitted fir purposes ofillustration. Here, the cavities 154 in the base plate 130 can be seenthat receive the posts 164 of the support body 128. Another feature thatcan be seen in FIG. 12 is the asymmetrical shape of the filter capacitor146 in this example, where one end is square and the opposite end iscurved outwardly. The base plate 130 has a matching asymmetrical recesswhich prevents the filter capacitor 146 from being inserted in the wrongorientation. For embodiments where one of the apertures of the filtercapacitor 146 is a ground aperture 161 where the ground plates 170 arepresent, this is significant because this prevents the ground aperture161 from being aligned with a feedthrough pin 136 because the ground pin160 should be present in the ground aperture 161 rather than afeedthrough pin 136.

FIG. 13 shows a protective body 174 that is attached to a partialconnector enclosure assembly that includes the base plate 130 and thefeedthrough pins 136, as well as the filter capacitor 146, support body128, and conductors 126 within the protective body 174. The protectivebody 174 protects the underside of the base plate 130, particularly theexposed conductors 126 that are intended to extend into the can of theIMD 102, during the construction, testing, transporting, and storage ofthe connector enclosure assembly 106. The protective body 174 may beconstructed of various rigid materials but where electrical testing isdesired, the protective body 174 is constructed of an insulator such asliquid crystal polymer to avoid short circuiting across the conductors126.

The protective body 174 includes a window 176 that exposes theconductors 126 so that electrical connection may be made to test theelectrical pathway between the conductors 126 and the individualelectrical connectors 132 as shown in FIG. 3. As shown in FIG. 14, theprotective body 174 may include two halves, a half 180 and another half178. In this example, a window 176 exists within the half 174 for accessto the conductors 126.

The protective body 174 may also includes features that allow the twohalves 178, 180 to be joined together while engaging the base plate 130.For instance, posts 184 and receptacles 186 may be provided where theposts are press fit into the receptacles as a flange 188 of each halfslides into place within a groove 190 on the base plate 130. This locksthe two halves 178, 180 together while locking the body 174 to the baseplate 130.

FIG. 15 shows a cross-sectional view which shows the relationship of anextended support 192 to the conductor 126. The support 192 extends overto the conductor 126 so as to provide a stop against movement of theconductor 126. Thus, the conductor 126 is protected from excessivemovement that could bend or break the conductor 126 such as duringassembly, testing, transport, and/or storage.

FIG. 16 shows the completed connector enclosure assembly 106 with theprotective body 174 being attached to the base plate 130 of theconnector enclosure assembly 106. At this point, the connector enclosureassembly 106 is ready for testing, transport, and storage while the canportion of the IMD 102 is being readied for attachment to the connectorenclosure assembly 106. When the time arrives for attachment, theprotective cover 174 is broken open using the holes 182 that are on bothsides of the protector halves 178 & 180. The assembly process of the IMD102 then proceeds.

One manner of assembling the IMD 102 that includes the featuresdiscussed above follows. It will be appreciated that this manner ofassembly is for illustrative purposes and that other manners ofassembling the IMD 102 are also possible. Initially in this example, theinner region where the feedthrough apertures 138 are located is weldedin place to an outer structure of the baseplate to complete thebaseplate assembly 130. The inner region contains the feedthrough pins136 passing through the ferrules 140 filled with the nonconductivepolymer 141 and with the insulator 158 being located underneath theferrule 140.

The filter capacitor 146 is then inserted with each feedthrough pin 136passing through an aperture 142. The support body 128 with theconductors 126 present therein is then positioned so that each conductor126 enters the region 144 of the aperture 142. The support body 128 isthen pressed into place such that the mounting posts 164 firmly lockinto the cavities 154 of the baseplate 130.

At this point, the feedthrough pins 136, conductors 126, and filtercapacitor 146 may be bonded by placing the solder split performs 149 inplace as shown in FIG. 5A. The filter capacitor 146 may also be bondedto the baseplate 130 at this time by placing a solder wire along theedge of the filter capacitor 146 between the filter capacitor 146 andthe base plate 130. The solder wire 150 and solder split performs 149are then reflowed to complete the partial connector enclosure assembly.The protective cover 174 is then installed as shown in FIG. 13. Thermal,shock, and electrical testing may then be performed. The partialconnector enclosure assembly is then ready for further assembly and maybe transported and/or stored prior to the time to complete the assembly.

At the next step, the nonconductive polymer 141 is added to the ferrules140 and then the medical adhesive 155 is applied to the top of thebaseplate 130. The feedthrough pins 136 are formed as necessary to be inposition to contact the electrical connectors 132. The pre-assembled setof electrical connectors 136, such as a Bal Seal® stack is then placedagainst the feedthrough pins 136 where they are then mechanically andelectrically interconnected.

A top portion of the connector enclosure 106 is then placed onto thebaseplate 130 and set of connectors 132. The set screw 134 is insertedinto position within the top portion of the connector enclosure 106. Acover plate of the connector enclosure 106 that covers an open side ofthe top portion of the connector enclosure 106 is put in position on thetop portion and against the baseplate 130. The top portion, cover plate,and the baseplate 130 are then seam welded, and the cavity within theconnector enclosure 106 is filled with a non-conductive polymer byinjection molding. At this point, the connector enclosure 106 is readyfor final assembly of the IMD 102.

During final assembly, the isolation cup 118 is placed into the bottomhalf of the can 108 as shown in FIG. 2. The electrical circuitry 122 isthen placed within the isolation cup 118, and the battery 120 is alsopositioned within the isolation cup 118.

The protective cover 174 is broken open to allow the connector enclosureassembly 106 to be removed from the protective cover 174. The connectorenclosure assembly 106 is then placed over the bottom half of the can108 and the conductors 126 are mechanically and electrically connectedto the electrical pads 124.

The bottom cap 116 is then added to the bottom half of the can 108. Thetop half of the can 108 is then placed into position relative to thebottom half. The interfaces of the two halves of the can 108, the bottomcap 116, and the baseplate 130 of the connector assembly 106 are seamwelded to complete the assembly of the IMD 102.

FIG. 17 shows another embodiment of an interconnection of a filteredfeedthrough. Here the feedthrough pins 136 pass through apertures in thebaseplate 130 and through a filter capacitor 220 as discussed for theprior embodiments. However, in this embodiment, the interconnection ofthe feedthrough pins 136 to the pads on the hybrid of the circuitrywithin the can is ultimately provided by conductors 206, 208. In thisparticular embodiment, these conductors 206, 208 are held in a fixedposition with respect to one another prior to being installed by beingformed together as an integral conductor unit 202 where each conductor206, 208 extends from a common tab 204. The integral conductor unit 202may be constructed of materials such as titanium, nickel, niobium,tantalum, platinum, MP35N® alloy, or other alloys thereof. Furthermore,the integral conductor unit 202 may include an outer layer that isplated or sputtered with material such as noble metals like gold orplatinum to allow solder wetting to the conductor 206, 208 to occurduring the soldering process.

The common tab 204 allows the integral conductor unit 202 to be easilygrasped and positioned during assembly of the structure shown in FIG. 17while the conductors 206, 208 maintain their relative spacing andorientation. Each conductor 206, 208 extends from the common tab 204 atthe proper spacing relative to the feedthrough pins 136 such that theconductors 206, 208 are more easily aligned and mated to thecorresponding feedthrough pins 136.

In this particular embodiment, the ends of the conductors 206, 208opposite the common tab 204 include annular rings such as the annularring 212 revealed for the conductor 208. The feedthrough pins 136 passthrough the openings of the annular rings 212. The annular rings arethen secured to the feedthrough pins 136. In the case of the groundconductor 206, the annular ring is secured to a ground pin 260 of thebaseplate 130. Thereafter, the common tab 204 is removed from theconductors 206, 208 such as by cutting or breaking the conductors 206,208 in vicinity of the common tab 204. For instance, the conductors 206,208 may be formed with a thinner section near the common tab 204 whichprovides a weak area that facilitates the cut or break.

There may be several ways to secure the conductors 206, 208 to theground pin 260 or feedthrough pins 136. For instance, in someembodiments, the conductors 206, 208 may be soldered to the respectivepin. As shown in FIG. 17, a pre-formed solder washer 210, 214 may bepositioned about the pin and onto the annular ring and then reflowed tocreate a bond that forms the physical and electrical coupling of theconductors 206, 208 to the pins. The solder washer for the annular ring212 has been omitted from FIG. 17 for purposes of illustrating theannular ring but would be included to provide the bond.

FIG. 18 shows the interconnection of some of the conductors to some ofthe feedthrough pins 136 once the solder has been reflowed to create thebond 214′. FIG. 18 also omits the washer 210 for the ground pin 260 tomore clearly illustrate the ground pin 260 in relation to the annularring 216 of the ground conductor 206. The reflowed solder 214′ of FIG.18 also flows into the opening of the filter capacitor 220 to create anelectrical coupling of the feedthrough pin 136 to a capacitor platewithin the filter capacitor 220. While FIG. 18 shows the feedthroughpins 136 as extending well beyond the annular rings 212, it will beappreciated that the feedthrough pins 136 may be trimmed to theappropriate length before or after the soldering has occurred in orderto achieve the final version shown in FIG. 21 which is discussed below.

Some embodiments of the annular rings 212 may include extensions and thefilter capacitor 220 may include keyhole shaped openings like that ofFIGS. 5B and 11 such that the extensions of the annular rings 212 enterthe keyhole area and are further soldered to the pin and capacitorplate. Likewise, for the embodiments discussed above with respect toFIGS. 5B and 10, those conductors 126, 162 may include annular ringsthat are positioned about the feedthrough pins as shown in FIGS. 17 and18.

An alternative manner of securing the conductors 206, 208 to the pins isshown in FIG. 19. Here, the bond of the conductors 206, 208 to the pins260, 136 is created by welding. In order to protect the filter capacitor220, protective washers 222, 224 are placed about the ground pin 260 andfeedthrough pins 136, respectively. These protective washers may beconstructed of a material such as alumina or glass to create aneffective barrier. However, prior to installation of the washers, thefeedthrough pins 136 are soldered to the capacitive plates of the filtercapacitor 220 by flowing solder into the openings 226 of the filtercapacitor 220. Then, the protective washers 222, 224 are put in place,followed by placement of the annular rings of the conductors 206, 208about the pins 260, 136. The annular rings are then welded to the pins260, 136. This configuration is illustrated in FIG. 20. While FIG. 20shows the feedthrough pins 136 as extending well beyond the annularrings 212, it will be appreciated that the feedthrough pins 136 may betrimmed to the appropriate length before welding has occurred in orderto achieve the final version like that shown in FIG. 23 which isdiscussed below.

A completed connector enclosure assembly 106 is shown in FIG. 21. Here,the annular rings of the conductors 206, 208 have been bonded to theground pin 260 and feedthrough pins 136, such as by reflowing solder214′ as shown, and the common tab 204 has been broken free anddiscarded. At this point, the conductors 206, 208 are ready to be bondedto pads of the hybrid.

FIG. 22 shows the connector enclosure assembly 106 upon being joined tothe hybrid circuitry 122 during assembly of the medical device 100′. Inthis particular example, the baseplate 130 has been bonded to one halfof the can while the conductors 206, 208 have been soldered to pads 124of the hybrid to complete the physical and electrical coupling of theconductors 206, 208 to the hybrid. As discussed above for otherembodiments, other manners of constructing the device 100′ are alsopossible, such as constructing the whole can separately, bonding theconductors 206, 208 to the pads 124, and then inserting the hybridcircuitry 122 into the assembled can while bonding the baseplate 130 tothe assembled can.

Another aspect that is present in the embodiment shown in FIG. 22 as arecess 228 within the filter capacitor 220 in proximity to atransitional section 230 of each conductor 208, where the transactionalsection extends from the annular ring to where the conductor 208 becomesapproximately perpendicular to the plane of the filter capacitor 220. Asshown in FIG. 23, the ground plate 232 of the filter capacitor 220 isexposed at the outer edges so that soldering electrically couples theground plate 232 to the baseplate 130. Furthermore, the ground plate 232may terminate to a metallic layer such as silver-palladium on theexterior side of the filter capacitor 220 that further allows the filtercapacitor 220 to be soldered to the baseplate 1130.

To ensure that the transitional area 230 of each conductor 208 does notelectrically short circuit to ground, the notch 228 is present in thefilter capacitor 220 to create additional airspace between the exposedarea of ground plate 232 where the ground plate 232 and any metalliclayer on the outer surface is soldered and the transitional area 230.While FIG. 23 shows an example where the annular ring has been welded tothe pin 136 with the protective washer 224 in place, it will beappreciated that his configuration of the filter capacitor 220 with thenotch 228 is also applicable to examples where the annular ring issoldered to the feedthrough pin 136.

While embodiments have been particularly shown and described, it will beunderstood by those skilled in the art that various other changes in theform and details may be made therein without departing from the spiritand scope of the invention.

1. An implantable medical device, comprising: a connector enclosureincluding a base plate having an aperture, the connector enclosurehousing at least one electrical connector; a can coupled to the baseplate, the can housing electrical circuitry; a filter capacitor coupledto the base plate, the filter capacitor having an aperture and havingcapacitor forming plates including a ground plate, the ground platebeing electrically coupled to the can; a feedthrough pin electricallycoupled to the electrical connector within the connector enclosure, thefeedthrough pin extending through the aperture in the base plate andbeing present in the vicinity of the aperture in the filter capacitor; aconductor with a first end being present in the vicinity of the aperturewithin the filter capacitor and with a second end extending into the canand electrically coupled to the electrical circuitry; and a body ofelectrically conductive bonding material being present within theaperture of the filter capacitor and creating an electrically conductivebond among the conductor, the feedthrough pin, and at least one of thecapacitor forming plates other than the ground plate.
 2. The implantablemedical device of claim 1, further comprising a support body that iscoupled to the base plate, wherein the conductor passes through thesupport body.
 3. The implantable medical device of claim 2, wherein thesupport body includes posts and the base plate includes cavities andwherein the posts are contained within the cavities.
 4. The implantablemedical device of claim 1, wherein the bonding material is solder or aconductive polymer.
 5. The implantable medical device of claim 1,wherein the second end of the conductor is directly bonded to a circuitboard within the can that contains the electrically circuitry.
 6. Theimplantable medical device of claim 1, wherein the filter capacitor hasan asymmetric shape and wherein the base plate includes a recess thatdefines an asymmetric shape that matches the asymmetric shape of thefilter capacitor.
 7. The implantable medical device of claim 1, whereinthe aperture within the filter capacitor has a keyhole shape and whereinthe feedthrough pin and the conductor pass into the aperture within thefilter capacitor.
 8. A method of manufacturing a connector enclosureassembly of an implantable medical device, comprising: providing aconnector enclosure including a base plate having an aperture, theconnector enclosure housing at least one electrical connector; providinga filter capacitor coupled to the base plate, the filter capacitorhaving an aperture and having capacitor forming plates; providing afeedthrough pin electrically coupled to the electrical connector withinthe connector enclosure, the feedthrough pin extending through theaperture in the base plate and being present in the vicinity of theaperture in the filter capacitor; providing a conductor with a first endbeing present in the vicinity of the aperture within the filtercapacitor and with a second end extending away from the filtercapacitor; and creating a single electrically conductive bond among theconductor, the feedthrough pin, and at least one of the capacitorforming plates.
 9. The method of claim 8, further comprising providing asupport body that is coupled to the base plate, wherein the conductorpasses through the support body.
 10. The method of claim 9, wherein thesupport body includes posts and the base plate includes cavities andwherein the posts are contained within the cavities.
 11. The method ofclaim 8, wherein the single electrically conductive bond is formed withsolder.
 12. The method of claim 8, wherein the second end of theconductor is directly bonded to a circuit board within the can thatcontains the electrically circuitry.
 13. The method of claim 8, whereinthe filter capacitor has an asymmetric shape and wherein the base plateincludes a recess that defines an asymmetric shape that matches theasymmetric shape of the filter capacitor.
 14. The method of claim 8,further comprising attaching a protective body to the base plate, theprotective body enclosing the conductor while having an aperture thatprovides access to the conductor.
 15. An implantable medical device,comprising: a connector enclosure including a base plate having anaperture and an integral ground pin formed as a machined feature of thebase plate, the connector enclosure housing at least one electricalconnector; a can coupled to the base plate, the can housing electricalcircuitry; a filter capacitor coupled to the base plate, the filtercapacitor having an aperture and having capacitor forming platesincluding a ground plate, the ground plate being electrically coupled tothe ground pin of the base plate; a feedthrough pin electrically coupledto the electrical connector within the connector enclosure, thefeedthrough pin extending through the aperture in the base plate andbeing electrically coupled to a filter capacitor other than the groundplate; a first conductor with a first end being electrically coupled tothe feedthrough pin and the filter capacitor other than the ground plateand with a second end extending into the can and electrically coupled tothe electrical circuitry; and a ground conductor with a first end beingelectrically coupled to the integral ground pin and with a second endextending into the can and electrically coupled to the electricalcircuitry.
 16. The implantable medical device of claim 15, furthercomprising a bond material forming an electrically conductive bond amongthe first end of the ground conductor, the ground plate, and theintegral ground pin.
 17. The implantable medical device of claim 15,further comprising a support body that is coupled to the base plate,wherein the ground conductor passes through the support body.
 18. Theimplantable medical device of claim 17, wherein the support bodyincludes posts and the base plate includes cavities and wherein theposts are contained within the cavities.
 19. The implantable medicaldevice of claim 16, wherein the bonding material is solder.
 20. Theimplantable medical device of claim 15, wherein the second end of theground conductor is directly bonded to a circuit board within the canthat contains the electrical circuitry.
 21. The implantable medicaldevice of claim 15, wherein the filter capacitor has an asymmetric shapeand wherein the base plate includes a recess that defines an asymmetricshape that matches the asymmetric shape of the filter capacitor.
 22. Theimplantable medical device of claim 15, wherein the ground aperturewithin the filter capacitor has a keyhole shape and wherein the integralground pin and the ground conductor pass into the ground aperture withinthe filter capacitor.
 23. An implantable medical device, comprising: aconnector enclosure including a base plate having an aperture and aground pin, the connector enclosure housing at least one electricalconnector; a can coupled to the base plate, the can housing electricalcircuitry; a filter capacitor coupled to the base plate, the filtercapacitor having a ground aperture and having capacitor forming platesincluding a ground plate, the ground plate extending to the groundaperture; a feedthrough pin electrically coupled to the electricalconnector within the connector enclosure, the feedthrough pin extendingthrough the aperture in the base plate and being electrically coupled toa capacitor plate other than the ground plate; a first conductor with afirst end being electrically coupled to the feedthrough pin and thefilter capacitor other than the ground plate and with a second endextending into the can and electrically coupled to the electricalcircuitry; a ground conductor with a first end being electricallycoupled to the ground pin and the ground plate and with a second endextending into the can and electrically coupled to the electricalcircuitry; and a body of electrically conductive bonding material beingpresent within the ground aperture of the filter capacitor and creatingan electrically conductive bond among the ground conductor, the groundpin, and the ground plate.
 24. The implantable medical device of claim23, wherein the ground pin is integral to the base plate.
 25. Theimplantable medical device of claim 23, further comprising a supportbody that is coupled to the base plate, wherein the ground conductorpasses through the support body.
 26. The implantable medical device ofclaim 25, wherein the support body includes posts and the base plateincludes cavities and wherein the posts are contained within thecavities.
 27. The implantable medical device of claim 23, wherein thebonding material is solder.
 28. The implantable medical device of claim23, wherein the second end of the ground conductor is directly bonded toa circuit board within the can that contains the electrically circuitry.29. The implantable medical device of claim 23, wherein the filtercapacitor has an asymmetric shape and wherein the base plate includes arecess that defines an asymmetric shape that matches the asymmetricshape of the filter capacitor.
 30. The implantable medical device ofclaim 23, wherein the ground aperture within the filter capacitor has akeyhole shape and wherein the ground pin and the ground conductor passinto the ground aperture within the filter capacitor.